In recent years, in the office environment, with the spread of computers, software, and networks, the amount of information available in the office has increased, and the amount thereof printed on print media, such as paper sheets, has also increased. In order to avoid the deterioration of the global environment due to cutting down of trees for use as the raw material to create paper, and to decrease the amount of CO2 generated in that production and the reduction of CO2 absorption when trees are cut down, reuse and recycling of paper sheets are desirable.
For example, a toner with decolorable property such as an electrophotographic toner including a coloring compound is known (JP-A-2010-191430, JP-A-2011-158901). A decolorable toner allows reuse of paper sheets since it is possible to erase, i.e., decolor and thus render non-visible to the human eye, the image printed on the paper. This process is known in the art as “decoloring”. However, such decoloring apparatus may not be used in conjunction with a non-decolorable toner. Thus, an apparatus which may use an ordinary non-decolorable toner together with such decolorable toner in one image forming apparatus is desired.
If the physical properties of the non-decolorable toner are sufficiently similar to the characteristics of the decolorable toner, it is possible to eliminate extreme temperature variations when fixing the decolorable and non-decolorable toner in the image forming apparatus, and it is possible to expect to efficiently print images using either the decolorable toner or the non-decolorable toner, or the decolorable toner or the non-decolorable toner together, in the same printing apparatus.